Mr. Ahmadinejad’s remarks were reminiscent of his comment two years ago that Israel should be “wiped off the map,” which caused outrage in the West.

In a speech on Sunday, Mr. Ahmadinejad said the Palestinian and Lebanese people had pressed the button to lead to Israel’s downfall.

“With God’s help, the countdown button for the destruction of the Zionist regime has been pushed by the hands of the children of Lebanon and Palestine,” he said.

He has often referred to the demise of Israel but has said that Iran does not pose a threat to it.

“If these remarks were indeed made, they are unacceptable,” said Bernard Kouchner, the French foreign minister. “I condemn them most firmly.” He added that Israel’s right to exist could not be called into question.

Spain, which was the host for talks last week between Iran and the European Union over Iran’s nuclear program, also quickly condemned Mr. Ahmadinejad’s comments.

Foreign Minister Miguel Ángel Moratinos said he had asked the ministry’s political director to express to Iran’s ambassador “our absolute, total rejection of those remarks.”